20397243071688 has 128 divisors (see below), whose sum is σ = 58580034416640. Its totient is φ = 5797613952000.

The previous prime is 20397243071687. The next prime is 20397243071773. The reversal of 20397243071688 is 88617034279302.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (20397243071687) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 39054433 + ... + 39573263.

It is an arithmetic number, because the mean of its divisors is an integer number (457656518880).

Almost surely, 2^{20397243071688} is an apocalyptic number.

20397243071688 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20397243071688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29290017208320).

20397243071688 is an abundant number, since it is smaller than the sum of its proper divisors (38182791344952).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20397243071688 is a wasteful number, since it uses less digits than its factorization.

20397243071688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 520059 (or 520055 counting only the distinct ones).

The product of its (nonzero) digits is 24385536, while the sum is 60.

The spelling of 20397243071688 in words is "twenty trillion, three hundred ninety-seven billion, two hundred forty-three million, seventy-one thousand, six hundred eighty-eight".